My pv feeds back into a SWER line with 12 houses , 3 active dairies and 3 parttime dairies. I very much doubt that any of my feed back would ever get back to the start of the line and even if it did would never get back to the area main substation . Produced here consumed here . Otherwise the power comes from Latrobe valley to morang , then dederang ,shepparton or snowy dartmouth or kiewa a distance of hundreds of kms with associated losses.On high use power days the coal "base load " is fully used say 6500mw everything over this is provided by consumable generation so Pv stops the use of gas , or water which can then be used later.so it is saving considerably for the grid.
thereare some very large pv systems around, bendigo has a 300kw array near the saleyards and many industrial buildings have large arrays (greater than 5kw which is the cut off for feed back)
If you actually are consuming power during sunlight hrs then pv is economic without any subsidies and the differential between peak and offpeak is starting to encourage people to use batteries charged off peak and used during peak . I saw someone with a nine hundred kg 48v forklift battery which he got for nothing as it had reached its 2 year "life" which he is connecting up on his house .

the swer lines I am talking about are the lower voltage line that run all over country victoria not interconeectors . All the brown coal generators in victoria are very large and total around 6500 mw which is much more than night loads and mostly much less rthan day peak loads . Pv provided power during the grids peak time and that power can remove fuel consumption from producing power . I was merely trying to point out that there a lot more pv around than only those attracting a premium feed back tarrif. All thermal plants have greatly reduced efficencies with large variations in load and that is one of the major problems in eastern australia as load variations are huge , even more so if the smelting industries were to be stopped .

On 19/08/2011 uwhp510 wrote:>On 19/08/2011 jammin wrote:>>Thats easy, automatic pumps that pump water uphill so that it can gravity>>feed later when you get home, this then drives a pelton wheel, that then>>feeds the energy into a battery array, that then powers the house whenever>>you need power ! simple>>Surely this system could be improved by the use of a few more energy conversions.>>eg.

On 4/09/2011 Cool Hand Lock wrote:>I've made $876 dollars in 12 months from a 1.5kw PV system, it only cost>$1750.>>If you don't install solar on your house your crazy.

My 5kw system returned $3690 last year and i have 3 rates to look at when i use power 66 cent feed back ,23.2 cent 7 to 11 monday to friday and 8.9 cent rest of time . It certainly makes you move consumption to the cheapest rate if possible .
Second array may or may not get the 66 cent feed back but it appears as it will be 25 cents though the non premium rate is 23.5 cent currently paying 24.3 7.00 am to 11 pm 9.9 overnight - will produce 7500to 8000kwh a year so return of $1760 min to max of $2000 though with power increases and carbon tax the consumptive rate will exceed the feed back so return will improve . System cost $15000 from which gst comes back and depreciates over 10 years for a minimum return of 12.9% on my immediate outlay . With the reduction in REC credit the system would be $700 dearer now if the price of panels has dropped

Congratulations on setting up your shop hopefully it will be very successful though the Vic governments stance on feed back is not very encouraging for people to install as an investment rather than a "footprint " decision .
The 25 cent feed back rate with a 5kw system will give 13% if all fed back , dropping from this if power is actually used if you are paying less than 25 cent a kwh .This is probably the case but come July with the carbon Tax it will most likely be above this . This will encourage people to consume their own power and not fed back into the grid during the daylight hours which is the peak demand time and why there is a feed back tarriff
In my case I effectively have 3 rates of power costs 66 cent from my pv, 23.4 cents 7 am to 11 pm Mon to friday and 10 cents rest of the time . Needless to say I have great incentive to move my consumption to the 10 cent option and within reason have done so .eg yesterday produced 31 kwh and fed back 23.9 kwh generating $17 nett to me

If you are installing pv make SURE you understand the tarriffs you will have , look at your present rate and what that will pay on feed back , THEN look at the premium feed back as this will most likely move you onto a time of use rate say 10 cents off peak 35 cents peak to get 25 cents "premium feed back ". Under this senario you could greatly increase your bill if you consume a lot of power and dont move your use to the off peak time . I met a woman who was consuming 15000 kwh per year who put in a 1kw pv which would produce 12 to 14 hundred kwh per year . To attract the 66 cent fed back they signed up on a time of use 35&10 cent per Kwh versus 21 before , and not surprising their bill has almost doubled as they haven't changed their time of use and truly believed that they would get rid of their power bill and extremely abusive to the power company as it was all because of the smart meter !!